All of the projects will make use of the microinjection facility to introduce macromolecules (primarily RNA and DNA) into cultured mammalian cells. Several of the projects will also make use of the electroporation facility as a more effective method of introducing exogenous genes into cultured cells. This centralized facility will provide equipment, supplies, and personnel for the whole program. This is a very cost effective way for all of the investigators to have access to techniques requiring skilled personnel and specialized equipment. Introduction of DNA into cells by electroporation will also be performed in this core. Each of the individual project leaders will be responsible for their own electroporation experiments. However, the technical personnel in this core will be trained in the use of the electroporation equipment and will be available to train and assist personnel from the other projects.